1. Field of the Invention
The present invention relates in general to an improved solution for removing mold and mildew stains from hard surfaces, that is also environmentally friendly.
2. Background Art
Mold and mildew stain removing solutions have been known and used to remove mold and mildew stains from a variety of hard surfaces found in the home, such as wooden and concrete floors, stainless steel, painted walls and ceilings, floor and bath tiles, as well as plastic, fiberglass, composite or laminated materials. Mold and mildew stains appear on many surfaces in the home, most frequently where water or humidity is present, such as in the bathroom, kitchen, or in basement areas. Standing water, water-damaged materials, or wet surfaces serve as a breeding ground for mold and mildew. Mold and mildew also grow in homes affected by floods and water leaks, which dampen household surfaces and provide areas for mold and mildew to grow. Typically, a small amount of a solution is sprayed onto a surface to remove the mold and mildew stain. After waiting a few minutes for the solution to penetrate the mold and mildew stain, it is then typically wiped away, using a cloth or paper towel.
Mold and mildew stain removing solutions traditionally contain a high amount of solvent, that itself would have a high vapor pressure. Such solutions have proven effective at penetrating large accumulations of mold and mildew, but are increasingly disfavored. First, high vapor pressure solvents can quickly flash off from the solution after they are applied, leaving the solution unable to penetrate a deep stain. To compensate for this, additional solvent is often required. Second, solvents with a high vapor pressure often emit an odor that is unpleasant for the user, which is amplified by its high concentration in the solution. Third, such solvents often emit high amounts of volatile organic compounds (VOCs) that are the subject of increasing regulation and public concern, which limits their use in household products. Fourth, many of the solvents that have traditionally been used in mold and mildew stain removing solutions are not biodegradable—a characteristic increasingly rejected by customers and regulatory bodies alike. One popular solvent used in traditional mold and mildew stain removing solutions is 2-butoxyethanol, also known as “EB”. EB has been cited by the Agency for Toxic Substances and Disease Registry for causing irritation of the nose and eyes, headache and vomiting. EB has also been found in at least 20 of the 1,430 National Priorities List (Superfund or Cleanup) sites identified by the Environmental Protection Agency.
Also, mold and mildew stain removing solutions have traditionally contained a higher pH level, such as 11.0 and higher. While high pH solutions have been effective at removing mold and mildew stains, their high pH levels pose problems for the cleaner, as well as for the surface that is being cleaned. First of all, direct contact with a high pH solution can dry out or even burn the skin; protective gloves must be worn by the user. Furthermore, the high pH solutions can also corrode hard surfaces while removing the mold and mildew stain. Prolonged exposure to a high pH cleaning solution can often result in corrosion to more delicate household surfaces.
It has also become important for mold and mildew stain removing solutions to be formulated in such a way as to have less impact on the environment (to be “green”). One way in which this is encouraged is through a program of the United States Environmental Protection Agency, known as the Design for the Environment Program (“DfE”). DfE certifies “green” cleaning products through the Safer Product Labeling Program. Another is through state regulatory bodies, such as the California Air Resources Board (“CARB”). Either through regulation, or through certification, these bodies set out standards for achieving environmentally friendly cleaning products. Among the standards, are the desire for a solution that is not as corrosive as prior art solutions, one having a lower pH. Further, the solution must minimize the emissions of VOCs, as well as the percentage of solvent that it may contain. Finally, the solution must contain only biodegradable products.
Accordingly, it is desirable to provide an effective mold and mildew stain removing solution, which is less corrosive than existing solutions for safer handling by the user, and to reduce the corrosive effects on household surfaces.
It is further desirable to provide an effective mold and mildew stain removing solution, that contains only biodegradable products, which are not malodorous, and meet all applicable environmental standards and regulations.
It is yet further desirable to find a mold and mildew stain removing solution which may be applied to hard surfaces, with a specific combination of surfactants, hydrotropes, solvents, chelating agents, preservatives and fungicides—all of which act in a synergistic manner to improve their effectiveness in removing mold and mildew stains.